Energy is
a. the same as mass.
b. the capacity to do work.
c. being constantly used up.
d. all of the above

B. The capacity to do work.  

Explanation:

That's the definition of energy.

A. is wrong. Energy is different from mass. However, according to Einstein's famous equation, energy can be converted into mass and vice versa.

C. is wrong. According to the Law of Conservation of Energy, it can be converted from one form to another, but it cannot be destroyed or created.

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."